Chukchi Sea — new walleye pollock fishing area

Schooling pattern of eastern Bering Sea walleye pollock and its impact on fishing behavior

Walleye pollock (Theragra chalcogramma) form persistent midwater and near-bottom schools in the daytime during the winter spawning season in the eastern Bering Sea (EBS). Two spawning areas in the EBS, north of Unimak Island and near the Pribilof Islands, are also the main fishing grounds. To study the schooling pattern of pollock and its impact on fishing behavior on these two fishing grounds,...

Update of Navarin walleye pollock stock assessment

Stock assessment model was so called effort-controlled version of the ISVPA-group of separable cohort models (for details of the model see appendix and references to it). This version of the model attributes residuals in cohort part of the model to errors in catch-at-age data, assuming that selection pattern (patterns) is stable. This version is often more robust for noisy catch-at-age data. Ad...

Environmental predictors of walleye pollock recruitment on the Eastern Bering Sea shelf

Spatial and temporal variance of walleye pollock (Theragra chalcogramma) in the eastern Bering Sea

Mobile acoustic surveys attempt to map and count aquatic organisms without biasing abundance estimates. Horizontal and vertical movements by target species may influence density measurements and net samples during acoustic surveys. To investigate the influence of fish movement on density data, we compared temporal and spatial variability of walleye pollock (Theragra chalcogramma) in three sets ...

Spatial and Temporal Variability in Size at Maturity of Walleye Pollock in the Eastern Bering Sea

—Size at maturity is incorporated into stock assessments of walleye pollock Theragra chalcogramma. For eastern Bering Sea walleye pollock, however, this important biological variable has not been examined since 1976 and possible interannual and geographic variations have never been evaluated. Maturity condition and fish length data were collected from 10,197 walleye pollock aboard factory trawl...